Field of the Invention
This invention relates to a method of treating brown coal for liquefaction and more particularly to an improvement in the preliminary treatment step of the brown coal liquefaction system, which improvement consists in efficiently removing moisture in raw brown coal and at the same time preventing the adhesion and accumulation of carbonates formed in the step of dehydration and/or of precipitate carbonates in the step of hydrogenation for liquefaction or effectively separating and removing such formed carbonates and the like in the step of hydrogenation for liquefaction and thereby increasing the liquefaction efficiency and the stability of continuous operation of the system.